The thought of bottling up children’s energy during the long winter months may make some parents nervous. But keeping kids active during the winter is as important as it is any other time of year, according to the Associated Press.

An estimated 9 million children are suffering from obesity in the United States, and some are calling it “one of the pandemics of the 21st century.”

Colder months can make maintaining healthy habits a little more difficult. AP reported that researchers believe kids burn just half as many calories in the winter as they do in the summer.

And while it may be more tempting for some kids to cuddle up on the couch than brave the elements, one of the best ways for parents to help their kids exercise is to be active with them, AP explains. Another way for parents to keep their kids moving, experts say, is to make the activities fun.

If you need a little inspiration for coming up with ideas to get kids off the couch, think “uncomplicated.” Dancing, housework, visiting an indoor pool or even walking around the mall are ways to avoid the cold and still exercise. If your children really need some fresh air, however, The Herald-Dispatch suggests sledding, hiking or having a good old fashioned snowball fight.

No matter what activity you choose for your kids, it has “to be something that gets the heart rate up,” Dr. Susan Adams explained to the Associated Press. Parenthood.com reports that kids need 60 minutes of exercise a day.